The cement of choice for most uses is Portland cement, a mixture of water, calcined lime and silica. Upon curing, the primary constituents of Portland cement are dicalcium silicate and tri-calcium silicate phases. In concretes, these silicate phases act to form the matrix that holds aggregate together. Portland cement is popular because it is inexpensive to produce and relatively easy to mix and pour if additional water (in excess of the normal amount required for the cement to react and cure, about a quarter of the weight of the dry constituents) is added thereto.
Part of the reason Portland cement is relatively inexpensive is because the silica component may come from a wide variety of sources, such as silica-containing clays, and also because these silica sources are not required to be especially pure or consistent. As all of its ingredients cement are inexpensive, Portland cement is ubiquitous as an industrial material and is by weight the most sold commodity in the world. However, since the purity and consistency of its ingredients are so poorly controlled, the use of Portland cement tends to yield materials with inconsistent properties which leads to additional expense due to the necessity for frequent repairs and reworking of structures incorporating poor cement.
Some of the disadvantages relating to Portland cement include:                inconsistent mixing        requires much more water to maintain a workable consistency than is ultimately required to hydrate and cure the resulting cementitious body        high porosity        high shrinkage upon drying        relatively slow set time        relatively slow hardening/curing time        unwieldy and labor intensive to convey, place, consolidate and finish        evolution of excess bleed water slows initial set and delays finishingAll other factors being constant, by using a reduced amount of mix water a slurry may be yielded that is more viscous and results in the formation of a cementitious body that is characterized by reduced less pore volume it and thus greater compressive strength. Conversely, by using excessive mix water, a cementitious body is produced that has a greater pore volume (necessitated by the requirement for the excess water to escape the body during the curing process); this excess porosity makes Portland cementitious bodies prone to spalling, flaking, and reduced compressive strength. Moreover, the residual porosity facilitates entry of water into the body, which may give rise to cracking if the water is subjected to cyclic freezing and melting, as well as to rusting rebar in reinforced concrete applications. The rusting effect is especially exacerbated when the invasive water is highly saline. Rebar rust likewise gives rise to the formation of cracks in the reinforced concrete, since rust has a greater volume than its constituent iron and water. Thus, excess porosity increases the likelihood of structural flaws that may even manifest themselves as sizeable pieces of the cementitious or concrete body breaking off; this effect is most often seen on roads and bridge decks on which de-icing salts have been used.        
Another type of cement is phosphate cement. Although phosphate cements tend to have excellent strength and hardness characteristics, as well as the additional advantage of adhering to other cured phosphate cement bodies and to most other materials (including Portland, gypsum, and aluminate cements, brick, metal, wood, most wood products, insulation, asphalt, tar paper, rebar, shingles and most roofing materials, organic membranes and some glasses) phosphate cements are not in common use because they tend to be much more expensive than ordinary Portland cements. Phosphate cements also have excellent chemical stability and compressive strength, and have toughness characteristics far superior to those of ordinary Portland cement. Moreover, phosphate cements tend to set up with little to no open porosity, and may therefore be used to form water resistant seals. Phosphate cements, like most ceramics, tend to be very refractive and electrically nonconductive, and thus make good thermal and electrical (and even acoustic) insulators.
Unlike in Portland cement, where the heat of hydration evolves slowly and then plateaus, the heat of hydration of phosphate cements spikes very quickly, with great heat evolution occurring promptly after the cement is mixed. This results in the phosphate cement setting up very quickly (too quickly for many commercial uses, since the working time may be measured in minutes or seconds) as the reaction is exothermic and often generates too much heat to allow phosphate cements to be workable for anything except small-scale applications, such as some road patching, as a dental cement, and the like. The exothermic acid/base reaction inherent in the curing of phosphate cements is quite mass intensive. Because they are quick setting, expensive and highly exothermic, phosphate cements are generally viewed as undesirable for most cement applications.
Thus, there remains a need for improving the control of cementitious slurries and/or liquid precursors, as well as for a means for controlling the characteristics of poured cementitious materials. The present invention addresses these needs.